Conventionally, in machine work by use of a machine tool, etc., required machining accuracy is realized by making a jig for deterring deviation of a reference point for each workpiece which is a machining object, and securing the workpiece at a specified position by means of the jig.
For this reason, machining errors tend to increase in the case of a workpiece which cannot be secured by means of the jig in the vicinity of its machining region.
Accordingly, PTL 1 describes a method for moving a machine to a correct position prior to further machine work, in which a position of a retroflector attached to an end effector such as a machine head is measured by using a 3D position sensor such as an interferometric laser tracker when the machine comes to rest, and a computer compares the measured position to a desired position according to machine media, to add appropriate revision to command statements.